Multi-dot enzyme-linked immunosorbent assay for serodiagnosis of trematodiasis

A nitrocellulose membrane strip dotted with crude antigens of trematodes, such as Paragonimus miyazakii, P. westermani, Fasciola sp., Clonorchis sinensis and Schistosoma japonicum was applied for serodiagnosis of trematodiasis. With peroxidase conjugated anti-human IgG and 4-chloro-1-naphthol as a substrate, antibodies in trematodiasis patient sera were clearly detected on the strip as bluish purple spots. Densities of the spots correlated well with values obtained by standard micro-ELISA. Cross-reactions among the trematode antigens, which is occurred more frequently than by ELISA, were observed with this method. However, the darkest spot correlated with the infecting parasite in all cases. With the high reliability and advantage that crude antigens can be used, this simple method, multi-dot ELISA, is considered to be useful for serodiagnosis of trematodiasis.